Machine for forming sheet-metal loops



Jam. 8, 1924. 1,480,122

J. R. S'EXTON MACHINE FOR FORMING SHEET METAL LOOPS Filed Sept. 27, 1922 5 Sheets-Sheet 1 Jan. 8, 1924. 1,480,122

- J. R. SEXTON MACHINE FOR FORMING SHEET METAL LOOPS 5 Sheets-Sheet 2 1% u l\ Mg 5 k Q w KW/d 4 A a g J figlul. k i

Flled Sept 27 J. R. SEXTON MACHINE FOR FORMING SHEET METAL LOOPS Jan. 8 1924.

Filed Sept. 27-, 1922 5 Sheets-Sheet 5 Jan. 8 1924.

J. R. SEXTON MACHINE FOR FORMING SHEET METAL LOOPS 5 Sheets-Sheet 4 Filed Sept. 27, 1922 J. R. SEXTON MACHINE FOR FORMING SHEET METAL LOOPS Jan, 8 1924;.

Filed p 27. 1922 5 Sheets-Sheet 5 Patented Jan. 8, 1924.

JOHN R. snX'roN, or HARrronn, ooN EotrioUr, assIGNon TO THE sEXnoN MACHiNE COMPANY, or nnn'rronn, CONNECTICUT, A CoRronArIoN or CONNECTICUT.

MACHINE FOB romaine sHEET-METAL nooPs.

Application filed September 27,1922. Serial No.-'590,963.

To all 20720110251; may concern:

Be it known that I, Jenn R. SnX'roN, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented a new and useful improvement in Machines for Forming Sheet-Metal Loops, o'l. which the fol-lowing is a specification.

This invention relates to machines of the class which feed a strip of sheet'metal, punch blanks from the fed strip, bend the blanks around a mandrel, fold free edges of the bent blanks together and then discharge the c'oiii'pleted loop thus formed. The sheet metal loops which the machine illustrated is especially designed to manufacture are those which are used in connection with carpet weaving machines.

The object of the invention is to provide a loop forming machine of this character which is cheap to build, simple to operate, durable in use and rapid in production.

The machine shown has a single stationary die and vertically reciprocated punch at the middle for cutting blanks from the fed strip, and two similar mechanisms, one on each side of the punch and-die for bending and folding the blanks. A carriage with two nests for receiving the punched blanks is reciprocated horizontally from side to sid'e'b'elow the die in such manner that every other blank is car ied by one nest to the bending and 1't'olding mechanism on one side and the alternate blanks carried by the other nest to the bending and folding mech anisms on the other side, the operating mechanisms being so timed that while one blank being carried to the bending and folding mechanisms on one side the nest on the other is returning for another blank.

In the accompanying drawings Figure 1 shows a front elevation of the machine. Fig. 2 shows a plan of the machine with the feeding and blanking mechanisms removed, the view being that looking down on the dotted line 2-2 on Fig. l. '3 shows on larger scale avertical section on the plane indicated by the dotted line 3 on Fig. 2, of the punch, die, carriage, slides, nests and bending and folding mechanisms, with the carriage at one limit of its travel. Fig. i is a similar view of one'end with the carriage moved toanother position. Fig. 5 a section on larger scale of the folding mechanism at one end. Fig. '6 is a similar view of the folding mechanism in an earlier position to that shown in Fig. 5. Fig. '7 is a vertical transverse section on the plane indicated by the dotted line 7-7 onv Fig. 2-. Fig. '8 shows a plan of a blank receiving nest and slide which carries the nest. Fig. 9 is a front View of thenestand slide. Fig. 10 is a vertical section on the plane indicated by the dotted line '1' 01O on Fig. 7 looking from the front of the machine. Fig. 11 is a plan of the carriage. Fig. 12 is a front view of the'carriage. Fig. 13 is a transverse section of the carriage on the plane of the line 1313 on Fig. 12. Fig. 14.- is a horizontal section'on "the plane indicated by the dotted line IP14 on Fig. 7. Fig. 15 is a view showing the mandrel about which the blank is bent. Fig. 16 is a View of the blank that is out by the punch and die from the fed strip. Fig. 17 is a View of the bent blank. Fig. 18 is a View of the bent blank with one edge folded. Fig. 19 is a view of the blank with bothedges told ed so as to form the completed loop.

The machine illustrated has a bed "20 at the middle of which is an upright bracket 21 that supports a vertically reciprocating punch 22. Below the punch is a die 23. [it the uper end of the punch is a roll 24 that is engaged by a cam 25 for driving the punch down through the die. The cam is fastened to a shaft 2-6 which isdriven inany suitable manner, as by the pulley 27. About the lower end of the punch and above the die is a guide 28 *through whichthe strip of stock 29 is fed. The feeding mechanism illustrated comprises the rolls 30 and 31 which are rotated at the proper intervals by the oscillation of the crank rod 82 that isconnected with the crank 33 on theshaft 26. This n1 cha-nis'm intermittently draws the strip of stock through the :guide above the die and below the punch which at the proper time is forced down so as "to, in cooperation with the die, out "the blank 34: from the stock.

Extending from side to side of the machine and mounted on :pillo-w blocks 35 on the top of the bed, is track plate 36. Slidably fitted on this -track is thecarriage 87. The carriage is connected by a rod 38 with a-crank 39. F a'stened to the c-rank is "a sprocket wheel 40 that -=is-'-'driven from the sprocket wheel 41 on the driving shaft 26 by the chain 42, Fig. 1. By this mechanism the carriage is reciprocated beneath the punch and die.

In a longitudinally extending mortise in the top of the carriage are two similar slides 43. Fastened to the top of each of these slides is a nest 44 which has a recess 45 the shape of the die opening and a groove 46, Figs. 8, 9.

When the carriage is at one limit of its travel the opening in one nest registers with the opening in the die and when the carriage is at the other limit of its travel the opening in the other nest registers with the opening in the die. The slides are thrust apart by a spring 47 located between them. On the under side of the outer ends of the slides are racks 48 and meshing with these racks are pinions 49 that are pivotally mounted on the carriage and that engage racks 50 loosely located in grooves 51 in the upper face of the track plate, Fig. 3. With this arrangement during the first part of the travel of the carriage toward the right the nest on the right hand slide is carried from beneath the die at twice the speed of travel of the carriage, for the pinion which engages with the rack of this slide besides being carried by the carriage is rotated by the rack in the track plate, which rack under these conditions butts against the spring plug 52 in the track plate. This rack remains in this position until the end 53 of the slide engageswith the wall 54 at the end of the carriage. As this slide can then move no further independently of the carriage the pinion stops rotating and locks these parts together so that they all continue the move ment at the speed of the carriage until the carriage reaches the limit of its movement toward the right. During the first part of this movement of the carriage toward. the right the slide with the nest on the left travels at the same speed as the carriage,

for the spring holds the slide back with its end 55 in contact with the wall 56 at the left hand end of the carriage and prevents the pinion on this side from rotating. As this pinion does not rotate the rack. in the track plate is moved along with the carriage until its end butts against the spring plug 57. Then as this rack in the track can move no further with the carriage the pinion on the left is rotated by the track rack as the carriage continues its movement, and ad vances the left hand slide against the pressure of the spring at twice the speed of the travel of the carriage, until the left hand nest registers with the die. When the carriage travels toward. the left the reverse of these movements follow, that is, the left hand nest first travels twice as fast as the carriage and then travels at the speed of the carriage while the right nest first travels at the speed of the carriage and then travels at twice the speed of the carriage. As one nest moves away from beneath the die the other is carried toward the die. The travel of both nests away from the die is first faster than the travel of the carriage and then the same as that of the carriage, while the travel of both nests toward the die is first the same as that of the carriage and then faster than the carriage.

@n each side near each end of the carriage is a vertical guide-way 58, Figs. 11, 12. Movable up and down in each guideway at the front of the carriage is a plate 59. (llamped in an opening in the upper end of each of these plates is the end of a thin mandrel 60 (l ig. 15) that extends toward the rear across the carriage above the slide. On a stud 61 at the lower end of each mandrel plate is a roll 62 (Fig. 7) which is free to rotate on and he slid in and out along the stud, Fig. 14. These rolls run in.

similar cam grooves 63 in plates fixed to the bed near the front. lVhen the carriage travels toward the right the roll at the left runs in the cam groove first at the level 64 and then is raised by the incline 65 to the level 66 so as to lift the mandrel. The roll runs at this upper level until the carriage completes its movement toward the right. However, just before this movement of the carriage is completed the roll engages the wedge surface 67 and is pushed over toward the front of the cam. Figs. 10, 14. When the carriage is returned toward the left this roll travels for a time at the upper level on the front of the cam until it reaches the inclined surface 68 10) by which it is forced down to the lower level of the cam. At this time the mandrel carried by the vertically movable plate bearing this roll is above the left hand nest and when it is drawn down it forces the blank into. the groove in the nest, bending the blank to the shape illustrated in Fig. 1.7. As the car riage nears the limit of its movement toward the left this mandrel roll engages the wedge surface 69 and is pushed back on the cam at the lower level, Fig. 14.

The mandrel raising and lowering mechanism at the right is a duplicate of that at the left and just described, except of course the cam groove is reversed, Fig. 1. "When the carriage starts to move toward the right the right hand mandrel is raised above the right hand slide.

As the right hand nest reaches a position under this mandrel the cam governing the roll on this side pulls the mandrel down and and causes it to bend the blank into the groove in that nest. l/Vhen the carriage moves toward the left this mandrel is down. but shortly the mandrel is lifted by the cam so as to be free from the nest and slide. In other words, as one mandrel is being carried the nest.

toward the die in its raised position the other mandrel is being carried away from the die in its lowered position.

As the mandrels are supported at one end only by the vertically reciprocating plates at the front, in order to leave the other end free so that the Completed l'oops which are folded around the mandrels may be pushed off, and as they are required to exert consid erable force when bending the blanks into the grooves in the nests, means for backing them when they act to force the blanks into the nest are provided. These ineans on each side are duplicates. Each consists of ayoke 5 T0 the downwardly extending legs of which are fitted to slide up and down in the vertical guide-ways 58 at the front and back near each end of the carriage. The front legs of the yokes are inside of the mandrel plates 59, Fig. '7. On the finder surface of the top of each yoke is a rib 71 that is designed when the yoke is drawn down to bear upon the top edge of the mandrel that is below it, igs. 3, 4:. The lower ends of'e'ach yoke support an arbor 72 which is adapted to slide back and forth in bearings 73. On each slidable arbor is a. roll 74 that rides between a cam plate 75 fixed to the bed and a cam plate 7 6 fixed to the nnder side of the track plate, Fig. 7. When the carriage travels toward the right the yoke roll at the'le ft runs along the front edge of the "cam plate "75 first 0n the surface 77 atone levehtlren when itreaches the inclined "surface 78 it is forc'ed down so as to bring the rib on the under side of the yoke down on the top of the mandrel. As the 'carriage "about reaches the end of its movement toward the right this roll engages the wedge surface 7 9 and is forced over at the same level to the back edge of the cam. When the carriage moves back toward the leftthe roll is held dewn the surface 80 on the earn plate 76 until it reaches the inclined surface 81 at which time it is drawn 'down "so as to force the mandrel beneath the 'yoke into the groove in Just hefore this 'roll reaches the end of its movement toward the. left it is raised for lifting the yoke and is pushed over toward the front 'of the ca-n1 at this level by the v'vedg'e surface 82, Figs. '3, 14. The cams for the (roll 'oftlie other yoke are the same except that they are arranged to operate reversely. VVhenthe carriage 'Inov'e's toward the right the roll of the right hand yoke is down "so'a's to causetheyokete bear upon the mandrel, Fig. 3. As "this roll travels along the hain runs ht this level until 'it reaches the incline '83 whieh caiis'e's the roll to bring the yoke down the same time the mandrel is brought down in order over toward the from edge (if the cam a the raised level, the wedge surface '84. By these mechanisms the mandrel's are firmly backed when forcing the blanks into the grooves in the nest and bending the blanks to 'U-shape, and atth'e proper time the yokes are raised so as to clear the folding mechanisms and also the ejecting mechanisms. v

At each side of the machine there is a mechanism for folding and overlapping the edges of the U-shaped blanks. These mechanisms are duplicates and therefore a description of one applies to the other. F ast'ened on the pillow block at each end of the bed is a plate 85 and secured to the under side of this plate and extending over the slide is the fixed folding bar 86. This bar is so located that as the slide with the blank bent into the nest by the mandrel passes 'under it during the'outward movement of the carriage the edge 87 of the blank on the dutside engages with the bar and is folded over the back edge or top of the mandrel, as shown in F 5. This leaves the blank in the form "shown in Fig. 18. As the slide moves inward after the outer edge of the blank has been folded the edgef8 8 of the blank on the inside is engaged by the pivoted folding bar 89 and folded down forinl the blank on the mandrel in the shape shown in Fig. 19. The pivoted folding bar is normally held down by a. plunger 90 under the thrust of the spring '91 in a socket in the folding plate (Fig. 5) but it is free to swing out of the wa of the edges of the blanks without folding them when the slide moves outward as shown in Fig. 6.

After both edges of the blank have been folded down "and the slide moves toward the punch and die a short distance, the yoke being raised at this time the folded blank is pushed "off of the mandrel by an ejector '92. The ejector is mounted so as to be movable toward the front and back across the carriage in the upper end of the mandrel Plate "on top of the mandrel, Fi s. 7, 10. At the front "end of the ejector is an ear 93 with a slot 94 in which is a roll 95 on the upper end of a lever 96 that is pivoted between lugs 97 which project toward the front from the carriage, Fig. 7. At the lower end of the lever is a roll 98 that runs in engagement with a c'am plate 99 fastened "on the top of the bed at the front. Co'- operating with this Cain plate is a pivoted cam 'l'atch 100 that is normally thrust back "by a'spring 101, Fig. 14-. There is 'an ejecting mechanism at. each end of the carriage and these mechanisms are duplicates. As the I carriage moves toward the right the roll at the ldwerend of the ejecting lever on the left engages the cam surf-ace 102 on the latch andtheleve iSOsCil l ttd'S O'bJS to cause "the ejector to move backward and push the blank from the mandrel. When the carriage moves toward the left the roll on the ejecting lever at the left passes back of the latch which yields for the purpose so that on this movement the ejector is not pushed backward. The ejector levers travel back and forth with the carriage as of course do the ejectors, and the ejectors move up and down with the mandrels, the slotted connection between the ejectors and the levers permitting this.

The production of articles on a machine of the character described is very rapid, for the blanks which are punched are carried alternately first to one side and then to the other side of the punch and die allowing the various movements of the bending and folding mechanisms to be performed concurrently upon two blanks with a consequent saving of time.

The. invention claimed is I l. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a nest for receiving the punched blanks, mechanism for reciprocating the nest toward and from the punching mechanism, a mandrel for bending the blanks into the nest, means engaged by the edges of the blanks as the nest is reciprocated for folding the edges of the blanks about the mandrel, and means for ejecting the folded blanks from the mandrel.

2. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a nest for receiving the punched blanks, mechanism for reciprocating the nest toward and from the punching mechanism, a mandrel for bending the blanks into the nest, mechanism for carrying the mandrel with the reciprocating nest, means engaged by the edges of the blanks for folding the edges of the blanks about the mandrel as the nest with the blanks is reciprocated, and means for ejecting the folded blanks from the mandrel.

3. A mechine for forming sheet metal. loops havin stock feeding and punching mechanisms, a nest for receiving the punched blanks, mechanism for reciprocating the nest toward and from the punching mechanism, a mandrel for bending the blanks into and holding the blanks in the nest, fixed means engaged by the edges of the blanks held in the nest by the mandrel as they travel back and forth for folding them about the mandrel, and means for ejecting the folded blanks from the mandrel.

4. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a nest for receiving the punched blanks, mechanism for reciprocating the nest toward and from the punching mechanism, a mandrel for bending the blanks into the nest mechanism for carrying the mandrel toward and from and with the nest, means engaged by the blanks held in the nest by the mandrel as the nest and mandrel reciprocate for folding the edges of the blanks about the mandrel, and means for ejecting the folded blanks from the mandrel.

5. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a nest for receiving the punched blanks, mechanism for reciprocating the nest toward and from the punching mechanism, a mandrel for bending the blanks into the nest, fixed means engaged by the edges of the blanks on one side of the mandrel as the blanks are carried in one direction by the nest for folding those edges over the mandrel, fixed means engaged by the edges of the blanks on the other side of the mandrel as the blanks are carried in the other direction by the nest for folding those edges over the mandrel, and means for ejecting the folded blanks from the mandrel.

6. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a nest for receiving the punched blanks, mechanism for carrying the nest toward and from the punching mechanism, a mandrel for bending the blanks into the nest, mechanism for carrying the mandrel with the nest, means engaged by the edges of the blanks for folding those edges over the mandrel as the nest is moved in one direction, means engaged by edges of the blanks for folding those edges over the mandrel as the nest is moved in the opposite direction, and means for ejecting the folded blanks from the mandrel.

7. A machine for forming sheet metal loops having stock feeding and punching mechanisms, nests for receiving the punched blanks, mechanism for carrying the nests alternately toward and from the punching mechanism, mandrels for bending the blanks into the nests, mean-s for folding the edges of the blanks about the mandrels, and means for ejecting the folded blanks from. the mandrels.

8. A machine for forming sheet metal loops having stock feeding and punching mechanisms, nests for receiving the punched blanks, mechanism for carrying the nests alternately toward and from the punching mechanism, mandrels for bending the blanks into the nests, mechanism for carrying the mandrels with the nests, means for folding the edges of the blanks about the mandrels as they are carried with the nests, and means for ejecting the folded blanks from the mandrels.

9. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a nest for receiving the punched blanks, mechanism for carrying the nest toward and from the punching mechanism, a mandrel for bending the blanks into the nest, means (to-operating with and assisting the mandrel to force the blanks into the nest, means for folding the edges of the blanks about the mandrel, and means for ejecting the folded blanks from the mandrel.

10. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a nest for receiving the punched blanks, mechanism for carrying the nest toward and from the punching. mechanism, a mandrel for bending the blanks into the nest, mechanism for carrying the mandrel with the nest, means engaged by. the edges of the blanks for folding those edges over the mandrel as the nest is moved from the punching mechanism, means engaged by the edges of the blanks for folding those edges over the mandrel as the nest is moved toward the punching mechanism, and means for ejecting the folded blanks from the mandrel.

11. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a nest for receiving the punched blanks, a slide carrying the nest, mechanism for moving the slide and nest toward and from the punching mechanism at a variable speed, a mandrel for bending the blanks into the nest, means for folding the edges of the blanks about the mandrel, and means for ejecting the folded blanks from the mandrel.

12. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, a slide movable on the carriage, a nest for receiving the punched blanks mounted on the slide, mechanism for reciprocating the carriage and carrying the nest toward and from the punching mechanism, a mandrel for bending the blanks into the nest, mechanism for carrying the mandrel with the nest, means for folding the edges of the blanks about the mandrel as it is carried with the nest, and means for ejecting the folded blanks from the mandrel.

13. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating the carriage, a slide on the carriage, mechanism for moving the slide independently of the carriage, a nest mounted on the slide for receiving the punched blanks, a mandrel for bending the blanks into the nest, means for folding the edges of the blanks about the mandrel, and means for ejecting the folded blanks from the mandrel.

14. A machine for forming sheet metal oops ha i ack feed n a P n mechanisms, a carriage, mechanism for reciprocating the carriage, a slide on the carriage, means on the carriage for reciprocating the slide, a nest for receiving the punched blanks mounted on the slide, a mandrel for bending the blanks into the nest, means for folding the edges of the blanks about the mandrel, and means for ejecting the folded blanks from the mandrel.

15. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating the carriage, a slide on the carriage, means for reciprocating the slide, a nest mounted on the slide for receiving punched blanks, a mandrel mounted on and movable with the carriage for bending. the blanks into the nest, mechanism for moving the mandrel up and down on the carriage, mean-s for folding the edges of the blanks over the mandrel, and means for ejecting the folded blanks from the mandrel.

16. A machine, for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating-the carriage, a slide on the carriage, means for reciprocating the slide, a nest mounted on the slide for receiving punched blanks, a mandrel mounted on and movable with the carriage for bending the blanks into the nest, means for moving the mandrel up and down on the carriage, a yoke mounted on and movable. with the'carriage for backing up. the mandrel, means for moving the yoke up and down on the carriage, means for folding the edges ofthe blanks over the mandrel, and means for greeting the folded blanks from the man- 17 A machinefor forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating the carriage, a slide on the carriage, mechanism for moving the slide independently of the carriage, a nest mounted on the slide for 1 receiving the punched? blanks, a mandrel mounted on and movable with the carriage for bending the blanks into the nest, means for folding the edges of the blanks about the mandrel, and an ejector mounted on and movable with the mandrel for ejecting the folded blanks from the mandrel. I

18. A machine for farming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for .reciprocating the carriage, a slide on the cari'iage, means on the carriage for reciprocating the slide at greater speed than the speed of the carriage, a nest for receiving the punched blanks mounted. on the slide, a mandrel for bending the blanks into the nest, means for folding the edges of the blanks about the mandrel, and means for ejecting the folded blanks fro m' the mandrel.

19. A machine for forming sheet metal loops having stock feeding and punching me hani ms ari ge, mechanism for reciprocating the carriage beneath the punching mechanism, slides on the carriage, means for reciprocating the slides alternately to and from the punching mechanism, blank carriers mounted on the slides for receiving punched blanks, mandrels mounted on and movable With the carriage for bending blanks into the carriers, means for folding the edges of the blanks over the mandrels, and means for ejecting the folded blanks from the mandrels.

20. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating the carriage beneath the punching mechanism, slides on the carriage, means for moving the slides independently of the carriage alternately to and from the punch ing mechanism, blank carriers mounted on the slides for receiving punched. blanks, mandrels mounted on and movable with the carriage for bending blanks into the carriers, means for folding the edges of the blanks over the mandrels, and ejector-s mounted on and. movable With the mandrels for ejecting the folded blanks from the mandrels.

21. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating the carriage beneath the punching mechanism, slides on the carriage, means on the carriage for reciprocating the slides alternately toward and from the punching mechanism at greater speed than the speed of the carriage, blank carriers for receiving punched blanks, mounted on the slides, mandrels for bending the blanks into the carriers, means for folding the edges of the blanks about the mandrels, and means for ejecting the folded blanks from the mandrels.

22. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating the carriage beneath the punching mechanism, slides on the carriage, means for reciprocating the slides alternately to and from the punching mechanism, blank carriers mounted on theslides, mandrels and means for backing the mandrels mounted. on and movable with the carriage also toward. and from the carriers, means for folding the edges of blanks over the mandrels, and means for ejecting the folded blanks from the mandrels.

23. A machine for forming sheet metal. loops having stock feeding and punching mechanisms, a carriage, mechanism for re ciprocating the carriage horizontally beneath the punching mechanism, slides on the carriage, means for moving the slides mdependently of the carriage alternately to and from the punching mechanism, blank carriers mounted on the slides vertically movable mandrels mounted on and movable With the carriage, vertically movable yokes mounted on and movable with the carriage over the mandrels, means for folding the edges of blanks over the mandrels, and ejectors for ejecting the folded blanks from the mandrels.

24. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating the carriage horizontally beneath the punching mechanism, slides on the carriage, means on the carriage for reciprocating the slides alternately toward and from the punching mechanism, blank carriers mounted on the slides. vertically movable mandrels mounted on the carriage, vertically movable yokes mounted on the carriage over the mandrels, means for folding the edges of blanks about the mandrels, and means for ejecting folded blanks from the mandrels.

25. A machine for forming sheet metal loops. having stock feeding and punching mechanisms, a carriage, mechanism for reciprocating the carriage beneath the punching mechanism, slides on the carriage, means for reciprocating the slides alternately to and from the punching mechanism, blank carriers mounted on the slides, mandrels and means for backing the mandrels mounted on and movable together With the carriage but movable independently of each other toward and from the carriers,means for folding the edges of blanks over the mandrels, and means for ejecting the folded blanks from the mandrels.

26. A machine for forming sheet metal loops having stock feeding and punching mechanisms, a carriage, mechanism for re ciprocating the carriage horizontally beneath the punching mechanism, slides on the carriage, a spring thrusting the slides apart, means for moving the slides independently of the carriage alternately to and from the punching mechanism, blank carriers mounted on the slides, vertically movable mandrels mounted on and movable With the carriage, vertically movable yokes mounted on and movable With the carriage over the mandrels, means for folding the edges of blanks over the mandrels, and ejectors for ejecting the folded blanks from the mandrels.

27. A machine for forming sheet metal loops having stock feeding and punching n'icchanisms, a carriage, mechanism for reciprocating the carriage horizontally beneath the punching mechanism, slides on the carriage, a spring thrusting the slides apart, pinions on the carriage for reciprocating the slides alternately toward and from the punching mechanism, blank carriers mounted on the slides, vertically movable mandrels mounted on the carriage, vertically movable yokes mounted on the carriage over the mandrels, means for folding the edges of the blanks about the mandrels, and means for ejecting folded blanks from the mandrels.

28. A machine for forming sheet metal loops having stock feeding and punching mechanisms, carriers movable on opposite sides toward and from the punching mechanism for receiving blanked stock, means on each side for bending blanks carried from the punching mechanism, means on each side for folding blanks as they are carried away from the punching mechanism, and means on each side for folding blanks as they are carried toward the punching mechanism.

29. A machine for forming sheet metal loops having stock feeding and punching mechanisms, carriers movable coincidently on opposite sides toward and from the punching mechanism for receiving blanked stock, means on each side for bending the blanks carried from the punching mechanism, means on each side for folding the blanks as they are carried away from the punching mechanism, means on each side for folding blanks as they are carried toward the punching mechanism.

30. A machine for forming sheet metal loops having stock feeding and punching mechanisms, carriers movable on opposite sides toward and from the punching mecha nism for receiving blanked stock, means on each side of the punching mechanism for bending the blanks, means on each side of the punching mechanism for folding the edges of the blanks.

31. A machine for forming sheet metal loops having stock feeding and punching mechanisms, carriers movable on opposite sides toward and from the punching mechanism for receiving blanked stock, means on each side of the punching mechanism for bending the blanks, means on each side of the punching mechanism beyond the bending mechanism for folding the edges of the bent blanks.

32. A machine for forming sheet metal loops having stock feeding and punching mechanisms, means for carrying punched blanks first away from and then toward the punching mechanism, and means on opposite sides of the punching mechanism for bending and folding the blanks thus carried.

33. A machine for forming sheet metal loops having stock feeding and punching mechanisms, means for carrying punched blanks first one side and then the other side of the punching mechanism, blank bending means on each side of the punching mechanism and blank folding means on each side of the punching mechanism.

34. A machine for forming sheet metal loops having stock feeding and punchin mechanisms, means for carrying punche blanks first one side and then the other side of the punching mechanism, blank bending means on each side of the punching mechanism, and blank folding means on each side beyond the bending means.

35. A machine for forming sheet metal loops having stock feeding and punching mechanisms, means for carrying punched blanks alternately to one side and then the other side of the punching mechanism, means for bending blanks on each side of the punching mechanism, and means for folding the blanks on each side beyond the bending means.

JOHN R. SEXTON. 

